1. Field of the Invention
The present invention relates to a sample analyzer for processing samples such as blood.
2. Description of the Related Art
A sample analyzer for aspirating a sample from a sample tube, which contains a sample such as blood or urine, through a pipette, and analyzing the sample is known.
If the sample analyzer is used for a long period of time, dirt may accumulate in the fluid system such as the pipette, a flow path, a valve, a reaction tube. This may cause lowering accuracy and triggers an operation failure. Thus, the fluid system needs to be cleaned periodically or for every predetermined number of processing samples. Such a cleaning of the fluid system in Japanese Laid-Open Patent Application No. 2003-254980 discloses a specimen analyzer for aspirating cleaning liquid contained in a liquid tube through the pipette to clean a fluid circuit inside.
Since the amount of cleaning liquid necessary for one cleaning is constant, to carry out the automatic cleaning, the liquid tube is filled with an amount of cleaning liquid same or greater than the necessary amount and is supplied to the specimen analyzer. The specimen analyzer described in JP2003-254980 is configured to aspirate from a cleaning liquid tube only the cleaning liquid of the amount necessary for one cleaning and use it to clean the fluid circuit. The redundant amount of cleaning liquid is discarded together with the cleaning tube or only the redundant cleaning liquid is discarded for reuse of the cleaning liquid tube. However, these operations may cause the cleaning liquid to spill out and attach to the clothes and hands of the operator. Or the smell of the redundant cleaning liquid may spread to the surrounding by volatilization.